The present disclosure generally pertains to power converters. Power converters, such as, for example, transformers, are typically used to convert electrical energy from one circuit into a suitable form for use in another circuit. Thus, power converters may be used to regulate voltage, current, or frequency between circuits. Typical power converters often utilize one or more input or primary coils positioned around a ferromagnetic core, and one or more output coils positioned around another portion of the core. The input coils are used to produce a magnetic flux in the core, which in turn produces an electromotive force, or voltage, in the output coil. However, due to the effect of Lenz's Law, the amount of output power produced by typical power converters does not exceed the amount of input power. Accordingly, a power converter which mitigates the effect of Lenz's Law on the input coils is desired.
Based on a standard demagnetization curve for permanent magnets, the flux density of the permanent magnet remains relatively constant until a magnetizing force sufficient to coerce the magnet is applied to the magnet, at which point the magnetic flux density drops quickly to zero. Thus, the permanent magnet acts as a constant magnetic flux generator until coerced. Furthermore, a variation of Kirchoff's current law states that magnetic flux in a series loop is constant. Therefore, the present disclosure sets forth an application of these principles wherein a permanent magnet is used to mitigate the effect of Lenz's Law in a power converter.
Embodiments of the present disclosure generally pertain to a magnetic power converter. A magnetic power converter in accordance with an exemplary embodiment of the present disclosure comprises a generally figure-8 shaped magnetic core having a plurality of legs. A toroid is positioned along at least one leg of the core and a permanent magnet is positioned along at least one leg of the core to provide a plurality of magnetic flux paths through the core, forming a balanced reluctance bridge. An output coil is positioned around one leg of the core, and at least one input coil is positioned around a portion of each toroid. When current is driven through the input coil, a control flux is induced in each toroid which remains captured in the toroid, increasing the flux density in the toroid and lowering the permeability of the core such that a virtual air gap is formed in each toroid. Such control flux in the toroid displaces the magnetic flux produced by the permanent magnet such that a portion of the magnetic flux from the permanent magnet flows through the third leg of the core.
The change in magnetic flux flowing through the third leg induces a current in the output coil which may be used to provide electrical power to a load. Thus, the control core acts as a variable reluctance shunt with respect to the magnet and the flow of electricity and none of the energy moderating the flux through the toroid is coupled to the output coil. Accordingly, the output coil is controlled by the input coils indirectly and the effect of Lenz's Law on the input coils is mitigated. Due to the absence of the effect of Lenz's Law on the input coils, any output loading is not reflected on the input. The output power may therefore be greater than the input power. Because of this ability to amplify input power, embodiments of the present disclosure may have wide applications in alternative energy and green energy generation.